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pigzsnout Mon Apr 22, 2013 4:51 pm

So I ran into a problem the other day when installing the cam gear, spacer, and distributor gear. After installing them, the keeper ring wouldnt go on. I had them pressed off, and reinstalled them since I guess I couldve screwed up the first time. After installing them the second time, I had the same problem. It appeared there needed about.040-.050 taken off the spacer for it all to fit.
These were all brand gears and the measured the exact same as a set of old junk german gears and spacer that were laying around. I know its not a problem with the gears. The problem is in the original crank machining. Does anyone have a crank laying around that can be measure? I need to know the full width of the main bearing journal from the end of the counterweight out to the edge of the journal. Also, the width of the journal where the gear rest from the main bearing journal to the inside edge of the keeper ring groove.
As I stated above, I ground down the spacer and got the keeper installed but I dont know if this is kosher since this will more than likely change how the distributor drive pinion will mesh with the gear. It seem that machining the top of the brass drive gear is a more suitable option. Am I correct or can I leave it as is?

VWNut_69 Mon Apr 22, 2013 4:57 pm

Your gear to drive the cam may be on backwards and they have a bevel on the inside edge so they seat down onto the crank journal.
First of all, can you see the timing marks on the crank gear? they should face towards the crankshaft pulley.
I will post a pic in a few minutes of mine.

Mike

pigzsnout Mon Apr 22, 2013 5:27 pm

Yes, the gear is installed correctly. Timing marks are facing up when crank is standing on the flywheel.

66brm Mon Apr 22, 2013 5:30 pm

I have an old CB crank in the shed I can measure up for you in a bit

VWNut_69 Mon Apr 22, 2013 5:35 pm

Hmmm, okay.
Bearing journal is 1.044" and from the circlip groove to bearing journal is 1.530".
Here is a pic of mine, you can see the gear is up against the bearing journal:


Is anything aftermarket? Gear? Spacer? , brass gear?
Mike

pigzsnout Mon Apr 22, 2013 6:13 pm

Geara are from a new EMPI install kit. Again they measure the exact same thickness as german gears. Spacer is a German spacer since I dont see the need for a racer spacer.
I just measured my crank but these are close but rough measuremrnts since the bearing and gears are installed.

Main bearing journal: 1.020
Space\gap between bearing face and timing gear: .150
Gear journal from the bottom of the timing gear to the top of the distributor gear: 1.545

VWNut_69 Mon Apr 22, 2013 6:29 pm

Can you post a pic similar to mine?
Mike

VWNut_69 Mon Apr 22, 2013 6:29 pm

Can you post a pic similar to mine?
Did you check the brass gear measurements?
Mike

pigzsnout Mon Apr 22, 2013 6:58 pm

VWNut_69 wrote: Can you post a pic similar to mine?
Did you check the brass gear measurements?
Mike

I dont know how to post pictures. PM me your email and I'll send you a few. The gears are somewhere in the neighborhood of.447 and .790. Granted my spacer has been ground down but the space between the 2 gears is .297

VWNut_69 Mon Apr 22, 2013 8:26 pm

How did you put the gear on? Heat it up and drop it on or press it on?

Mike

pigzsnout Tue Apr 23, 2013 9:34 am

VWNut_69 wrote: How did you put the gear on? Heat it up and drop it on or press it on?

Mike

Gears were pressed on.

[email protected] Tue Apr 23, 2013 9:46 am

What brand crankshaft is it? I had a problem a couple years ago with two different manufacturers. I had to sand down the brass gear about .040-.050 for the gear stack to fit.

pigzsnout Tue Apr 23, 2013 4:37 pm

[email protected] wrote: What brand crankshaft is it? I had a problem a couple years ago with two different manufacturers. I had to sand down the brass gear about .040-.050 for the gear stack to fit.

Its an old school Small Car Specialties forged 78.4. Do you feel that its better to remove the .aterial from the brass gear instead of the spacer like I did??

mark tucker Tue Apr 23, 2013 8:19 pm

I wonder if the crank gear has enough raidi/chamfer to go down far enough?I dont see any issue doing it your way or thining out the brass gear.( I would thin the steel racer spacer).
is it possiable the gear wasent pressed on far enough?(I hope the crank was supported properly for this procedure,I like the heating of the gear best)

VWNut_69 Wed Apr 24, 2013 5:50 pm

Pigzsnout sent me his pics to post, it looks like the distributor gear is a bit wide:





Mike

pigzsnout Wed Apr 24, 2013 6:32 pm

Thanks Mike. I hope trimming down the spacer as I did resolved the issue and doesnt compound into further crank or timing problems once the engine is installed.

66brm Wed Apr 24, 2013 6:39 pm

Is the short block together yet? if not it may be an idea to engineer blue the distributor drive gear and check the contact pattern with the dist installed in the case half, just in case something doesn't quite line up right

pigzsnout Wed Apr 24, 2013 8:13 pm

66brm wrote: Is the short block together yet? if not it may be an idea to engineer blue the distributor drive gear and check the contact pattern with the dist installed in the case half, just in case something doesn't quite line up right

No. Tonight I just finished tapping the oil galley plugs and the got full flow fitting set properly. Now the case is ready for assembly

miniman82 Thu Apr 25, 2013 3:28 am

Do what I did: clearance the cheapest part, I.E. the brass gear. If you take .020" from each side of it, I doubt it will notice.

mark tucker Thu Apr 25, 2013 8:37 am

and what differance does taking .020 from each side make???none.the gear is brass,Ive sen cracked ones,I would leave all the brass there that I could. thus trim the spacer, Ive had them a bit more than others.I also like the gear&clip to be intarfearance to help hold the clip.I also add a bend or two to the clip.I have a scat crank where the grove wasway too deep&the clip was loose, that will tighten it up.on the sides of the groove.getter done and go have fun.



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